Detergent formulations

ABSTRACT

DETERGENT FORMULATIONS COMPRISING TETRA ALKALI METAL ETHENE TETRACARBOXYLATE AS A DETERGENCY BUILDER IN COMBINATION WITH CONVENTIONAL SURFACTANTS PROVIDE EFFECTIVE CLEANING ACTION.

United States Patent 3,689,418 DETERGENT FORMULATIONS Russell D. Harken,St. Louis, Mo., assignor to Monsanto Company, St. Louis, M0. N0 Drawing.Filed Jan. 18, 1971, Ser. No. 107,468

Int. Cl. Clld 1/12 US. Cl. 252-89 '3 Claims ABSTRACT OF THE DISCLOSUREBACKGROUND OF THE INVENTION This invention relates to novel detergentformulations characterized by the use therein of tetra alkali metalethene-1,l,2,2-tetracarboxylate as a detergency builder in combinationwith conventional surfactants.

The basic and essential ingredient of any detergent formulation is asurfactant which by reason of its surface active characteristics insolution, wetting properties, foaming properties, emulsifying actionand/or other properties is effective in removal of soil or dirt.

Detergent formulations commonly contain at least one other ingredientserving as a adjuvant, re-enforcer, supplement, augmentor, potentiatorand/or beneficator which serves to improve or enhance the cleansingability of the formulation in various applications. Such otheringredients are usually referred to as detergency builders.

In addition to providing adequate functional charac-' teristics, it isdesirable that the ingredients of detergent formulations be free ofadverse ecological effects, at least in those instances where theingredients will be released into the environment. For example, it isdesirable that organic ingredients of detergent formulations be capableof bio-degradation in conventional sewage processing operations.Further, it has been suggested that the quantities of phosphoruscontained in detergency builders may contribute to eutrophicationprocesses. Accordingly, it may be ecologically desirable to providedetergency builders of reduced phosphorus content.

SUMMARY OF THE INVENTION It is object of this invention to provide noveldetergent formulations.

These formulations comprise a surfactant and tetra alkali metal ethene1,1,2,2 tetracarboxylate. The tetra alkali metalethene-l,1,2,2-tetracarboxylate in addition to providing detergencybuilder function is free from phosphorus and substantially totallybio-degradable in activated sludge treatment such as utilized in manysewage processing operations.

The invention will be better understood from the following descriptionof the preferred embodiments.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The detergent formulations ofthis invention will contain from 1% to 60% by weight, preferably from 5%to 40% by weight, of tetra alkali metal ethene-1,l,2,2-tetracarboxylate.The tetra sodium salt is generally preferred.

The tetra alkali metal ethene-1,l,2,2-tetracarboxylate can be preparedby treating diethyl bromomalonate with sodium carbonate followed bybasic hydrolysis of the tetraethyl ester according to procedures such asdescribed by Malachowski and Sienkiewiczowa, Ber., 68, 33 (1935) and inOrganic Synthesis, coll. vol. II, p. 273 (1943).

Patented Sept. 5, 1972 The tetra alkali metalethene-l,1,2,2-tetracarboxylate can be utilized as the sole detergencybuilder in the compositions of this invention or in combination withother known detergency builders such as water-soluble, inorganic buildersalts, for example, alkali metal carbonates, borates, phosphates,polyphosphates, bicarbonates and silicates or organic builders, forexample, alkali metal, ammonium or substituted ammonium,aminopolycarboxylates, salts of pyhtic acid, sodium citrate,water-soluble polymeric polycarboxylates as described in US. Pat.3,308,067 and the like. Examples of such other known builders which havebeen extensively utilized commercially include sodium tripolyphosphateand sodium nitrilotriacetate.

The detergent formulations of this invention will additionally containat least 8% by weight of a surfactant. Any of the numerous well-knownanionic, nonionic, zwitterionic or ampholytic surfactants can beemployed.

Examples of suitable anionic surfactants include alkyl ethyl sulfonates,alkyl sulfates, acyl sarcosinates; acyl esters of isethionates, acylN-methyl taurides, and alkyl aryl sulfonates. The foregoing materialsare used in the form of their water-soluble sodium potassium, ammoniumand alkyl ammonium salts. Specific examples include sodium laurylsulfate; sodium N-methyl lauryl tauride; sodium dodecyl benzenesulfonate; and triethanol amine undecanol benzene sulfonate.

Examples of suitable nonionic detergents include alkyl phenol andalcohol alkoxylates including condensates of l-decanol or l-undecanolwith from 3 to 5 molecular proportions of ethylene oxide such asdescribed in US. patent application Ser. No. 707,480 filed Feb. 23, 1968and copending herewith; condensates of monohydroxy or polyhydroxyalcohols such as oleyl alcohol or 1 tridecanol with from 9 to 15molecular proportions of ethylene oxides; alkyl internal vicinaldialkoxy or hydroxy alkoxy compounds as described in US. patentapplication Ser. No. 852,898 filed Aug. 25, 1969 and copending herewith;and condensates of alkylene oxides with organo amines, for example,ethylene diamine and amides such as N-octadecyl diethanol amide.

Examples of cationic surfactants include octadecyl ammonium chloride;straight chain fatty amines having 8 to 18 carbon atoms; and quaternaryammonium compounds such as octadecyl trimethyl ammonium chloride.

Suitable ampholytic surfactants include the amido alkene sulfonates suchas sodium C-pentadecyl, N-methyl amido ethyl sulfonate potassium C-octylN-naphthalene amido propyl sulfonate; ammonium C-decyl, N-cyclo propylamido butyl sulfonate, and aliphatic amine derivatives in which thealiphatic substituent contains an anionic water-solubilizing substituentsuch as a carboxy, sulfo, phosphato, or phosphino group, for example,sodium-3-dodecyl amino propionate and sodium-3-dodecyl amino propanesulfonate,

Examples of zwitterionic surfactants include derivatives of quaternaryammonium phosphonium and sulfonium compounds such as3-(N,N-dimethyl-N-hexadecyl ammonio) propane-l-sulfonate and3-(N,N-dimethyl-N-hexadecyl ammonio-Z-hydroxy propane-l-sulfonate).

It will be understood that the above examples of supplementarysurfactants are by no means comprehensive. Numerous other surfactantsare known to those skilled in the art are set forth in such familiarreferences as Surface Active Agents by A. M. Schwarz and James W. Perry.It will be further understood that the use of such surfactants will bein accordance with conventional, wellunderstood practices of detergentformulation. For example, cationic and anionic detergents will notnormally be employed in combination due to recognized problems ofprecipitation of insoluble products.

Since the alkali metal ethene tetracarboxylate builder is substantiallytotally bio-degradable, preferably the surfactant chosen will besimilarly bio-degradable.

In accordance with general practice, the ratio of the deter'gencybuilder components to the surfactant components will be in the range offrom 1:2 to about 12:1 by weight.

In addition to surfactant and builder components, the detergentformulations of this invention may contain fillers such as sodiumsulfate and minor amounts of bleaches, dyes, optical brighteners, soilanti-redeposition agents, perfumes and similar conventional detergentformulation additives.

The invention is further illustrated by the following ex ample whereinall parts and percentages are by weight unless otherwise indicated.

EXAMPLE Detergent formulations are prepared containing about 17 partslinear sodium alkylbenzene sulfonate having an average molecular weightof about 230; 8.5 parts silicate having a 1:2 ratio of Na O:SiO 24.5parts sodium sulfate and 50 parts tetra sodiumethene-1,1,2,2-tetracarboxylate. This composition is compared incleaning effectiveness on polyester/cotton and cotton fabrics with anotherwise identical composition containing no tetra sodium ethene-1,1,2,2-tetracarboxylate. Detergency performance of the formulationscontaining the builder as determined by measurement of the difference inreflectance of washed and unwashed samples averages more than 30% better30 tained with formulations containing 25 parts and 38 parts tetrasodium ethene-l,1,2,2-tetracarboxylate. I

What is claimed is:

1. A detergent composition consisting essentially of at least 8% byweight of a surfactant selected from the group consisting of anionic,nonionic, zwitterionic, and ampholytic surfactants and from 1% to 60% byweight tetra alkali metal ethene-l,1,2,2-tetracarboxylate.

2. The composition of claim 1 wherein said tetra alkali metalethene-1,l,2,2-tetracarboxylate is tetra sodiumethene-l,1,2,2-tetracarboxylate.

3. The composition of claim 2 wherein said tetra sodiumethene-1,1,2,2-tetracarboxylate is present in an amount of from 5% to40% by weight.

References Cited UNITED STATES PATENTS 2,264,103 11/ 1941 Tucker 210232,311,008 2/1943 Tucker 21023 3,459,670 8/ 1969 Carter 252-99 3,580,5825/1971 Yang 252-135 OTHER REFERENCES Chem. Absts., vol. 52, p. 16192.

LEON D. ROSDOL, Primary Examiner P. E. WILLIS, Assistant Examiner US.Cl. X.R.

